One vertex per element, one color per generator, with an edge from x to x·s.
(2,7)(3,8)(4,5)(9,10)(11,19)(12,16)(13,22)(14,17)(15,20)(18,23)(21,24)(25,26,29,32)(27,30,34,37)(28,31,35,38)(33,39,40,36)(1,2,6,3)(4,8,5,7)(9,11,14,12)(10,15,17,24)(13,21,23,20)(16,22,19,18)(25,27,29,34)(26,30,32,37)(28,33,35,40)(31,36,38,39)(1,3,6,2)(4,8,5,7)(9,12,14,11)(10,16,17,19)(13,21,23,20)(15,22,24,18)(25,28)(26,31)(27,33)(29,35)(30,36)(32,38)(34,40)(37,39)(1,4,6,5)(2,8,3,7)(10,17)(11,12)(18,22)(20,21)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.